Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Heavy metal or aluminum in an organic phosphorus compound...
Reexamination Certificate
2002-08-21
2004-07-27
McAvoy, Ellen M. (Department: 1764)
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Heavy metal or aluminum in an organic phosphorus compound...
C508S375000, C508S470000, C508S545000
Reexamination Certificate
active
06767871
ABSTRACT:
TECHNICAL FIELD
This invention provides a combination of anti-wear agents and polymers to form diesel engine lubricants with unique boundary films in the presence of abrasive contaminants.
BACKGROUND OF THE INVENTION
In order to prevent wear, lubricants may form sacrificial films on rubbing surfaces. Zinc dialkyl dithiophosphates (ZDDP) are the most common anti-wear agents used in lubricants that act in this manner. However, in modern diesel engines and in off-road applications contaminants are usually present in the lubricant and can cause abrasive wear. The sacrificial films formed by lubricant additives must therefore be tenacious. We have discovered that there are specific combinations of ZDDP and polymers that can work synergistically to form tenacious boundary films. Zinc dialkyl dithiophosphates are well known in the art. For example, see U.S. Pat. Nos. 4,904,401; 4,957,649 and 6,114,288, which are incorporated herein by reference in their entirety.
SUMMARY OF THE INVENTION
This invention is a lubricating oil composition comprising a major amount of an oil of lubricating viscosity and a minor amount of a combination of at least one functionalized polymer, and at least one zinc dialkyl dithiophosphate (ZDDP), wherein the ZDDP is made from a mixture of primary alcohols or a mixture of primary and secondary alcohols, wherein the lubricating composition has a high boundary film result as measured by using a High Frequency Reciprocating Rig (HFRR), of greater than or equal to 15, preferably greater than 20, more preferably greater than 30, and most preferably greater than 60.
Preferably, the lubricating composition has a viscosity suitable for use in lubricating a diesel engine. Also, the preferred functionalized polymers are an amine-capped, grafted olefin copolymer or a copolymer of non-functionalized and functionalized methacrylate monomers. Preferably, the ZDDP is made from a mixture of primary alcohols or a mixture of primary and secondary alcohols.
REFERENCES:
patent: 3915871 (1975-10-01), Bryer et al.
patent: 3923669 (1975-12-01), Newingham et al.
patent: 4101428 (1978-07-01), Crawford
patent: 4455243 (1984-06-01), Liston et al.
patent: 4466895 (1984-08-01), Schroeck
patent: 4606834 (1986-08-01), Hart et al.
patent: 4904401 (1990-02-01), Ripple et al.
patent: 4957649 (1990-09-01), Ripple et al.
patent: 5075383 (1991-12-01), Migdal et al.
patent: 5112509 (1992-05-01), Brink et al.
patent: 5139688 (1992-08-01), Nalesnik
patent: 5238588 (1993-08-01), Nalesnik et al.
patent: 5534175 (1996-07-01), Cantiani
patent: 5955405 (1999-09-01), Liesen et al.
patent: 5972853 (1999-10-01), Boffa et al.
patent: 6004910 (1999-12-01), Bloch et al.
patent: 6010986 (2000-01-01), Stachew et al.
patent: 6107257 (2000-08-01), Valcho et al.
patent: 6107258 (2000-08-01), Esche et al.
patent: 6114288 (2000-09-01), Fujitsu et al.
patent: 6569821 (2003-05-01), Ibrahim et al.
patent: 2001/0036906 (2001-11-01), Locke et al.
patent: 0 206 748 (1986-12-01), None
patent: 0 277 729 (1988-08-01), None
patent: 1 195 427 (2002-04-01), None
“Wear Mechanism in Cummins M-11 High Soot Diesel Test Engines,” by C.C. Kuo, C.A. Passut, T-C Jao, A.A. Csontos and J.M. Howe (SAE Technical Paper 981372).
Devlin Mark Thomas
Esche, Jr. Carl K.
Loper John T.
Passut Charles A.
Ethyl Corporation
McAvoy Ellen M.
Rainear Dennis H.
Robinson Leah O.
LandOfFree
Diesel engine lubricants does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Diesel engine lubricants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Diesel engine lubricants will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3191560